With the enactment of the Clean Air Act and the regulations passed relative to the contents of the exhaust gas of a vehicle, there has been a continual search for a simple and economical means for reducing the pollutants discharged into the atmosphere. Presently, the automotive industry relies on catalytic converters placed in the exhaust line to comply with the regulations. Obviously, the use of these converters has its attendant problems, for example, they are expensive due to the fact that costly material such as platinum must be used therein; they add more weight to the vehicle, they discharge noxious sulfide odors, they reduce the overall efficiency of the vehicle; they require more gasoline to be used; they cause exhaust back pressure problems; they are only effective at high temperatures and consequently cannot be allowed to stand idle as they have been known to cause grass fires and to melt asphalt when sitting over the same, and to kill people within the vehicle from carbon monoxide fumes due to incomplete combustion, etc.
In this regard, and in the known prior art, U.S. Pat. No. 2,664,864 broadly discusses removing conventional heat from the manifold and supplying a fuel mixture at a relatively low intake temperature thus resulting in a denser charge. However, the patentee lowers the temperature of the fuel-air charge by mounting the intake distributing chambers away from the exhaust manifold and by providing and heating a dam adjacent the intake valve to insure complete vaporization, see Column 2, lines 11-20; lines 45-54. At Column 3, lines 30-35, the patentee further states that his invention is more suitable for an engine wherein the exhaust is disposed oppositely the intake ports. Therefore, and in conclusion, it can be stated that while the patentee spoke of a cooler fuel-air charge, he did not realize the full significance of the same as there is residual heat involved due to the fact that the intake chambers are in metal-to-metal contact with the engine block.
In U.S. Pat. No. 2,573,095 the patentee discloses an intake manifold spaced from the engine wherein, hopefully, the gases therein are maintained as cool as possible, see Column 1, lines 53-56; at Column 3, lines 70-74, the patentee further states that the manifold is still in heat exchange relationship with the engine block via conduits 17, 17a and 17b and at Column 4, lines 5-10, he further states that the manifold should be made from material having a high heat conductivity. At Column 5, lines 5-8, the patentee does mention there are advantages to cooling the fuel and air mixture, however, he further states that the air utilized is apparently heated to insure vaporization. In this regard, while the patentee realizes advantages to a cooled fuel-air charge he still maintains his manifold in heat exchange relationship with the engine block and utilizes elaborate cooling fins and reflecting surfaces in order that the gases therein be "relatively cool" as specified in the claims.
U.S. Pat. No. 3,561,408 is also known as showing a separate manifold, but like the prior art patents, the same is in heat-conducting relationship with the engine block and therefore has all the attendant deficiencies of said aforementioned patents.
U.S. Pat. No. 2,730,339 discloses a fuel distributing system wherein the fuel-air mixture is fed into successive cylinders via individual tubes connecting the carburetor thereto. As noted, there is no suggestion of introducing a cold charge of a fuel-air mixture into the cylinders.